Noroviruses are a leading viral cause of epidemic and sporadic acute gastroenteritis in humans of all ages,causing substantial illness and death.Each year,noroviruses cause ≈21 million infections in the United States and≈200,000 deaths worldwide.Among the 6 known norovirus genogroups(GⅠ-Ⅵ),all GⅠ,most GⅡ,and a few GⅣ noroviruses infect humans(humannoroviruses).Each genogroup includes up to 22 genotypes based on the sequences of major capsid protein 1(VP1).Although GⅡ.4 noroviruses were predominant globally for 2 decades,the previously rare GⅡ.17 genotype emerged during the 2014-15 epidemic season in China and other Southeast Asian countries/regions,causing major epidemics of acute gastroenteritis.Infection of domestic pigs,cattle,dogs,and rhesus macaques with human norovirus has been reported.We report the detection and characterization of norovirus GⅡ.17 that extensively and naturally infected farm-raised rhesus monkeys in southwestern China.